The amount of video data needed to depict even a relatively short film can be substantial, which may result in difficulties when the data is to be streamed or otherwise communicated across a communications network with limited bandwidth capacity. As a result, video data is generally compressed before being communicated across modern day telecommunications networks. Video compression devices often use software and/or hardware at the source to code the video data prior to transmission, thereby decreasing the quantity of data needed to represent digital video images. The compressed data is then received at the destination by a video decompression device that decodes the video data. With limited network resources and ever increasing demands of higher video quality, compression and decompression techniques that improve compression ratio with little to no sacrifice in image quality are desirable.
A video coding system may comprise an encoder that transforms an input video into a compressed representation suited for storage/transmission and a decoder that can uncompress the compressed video representation back into a viewable form. The encoder may discard some information in the original video sequence in order to represent the video in a more compact form, for example, to enable the storage of the video information at a smaller volume and transmission of the video information at a lower bitrate than otherwise might be needed.
Various technologies for providing three-dimensional (3D) video content are currently investigated and developed. Especially, intense studies have been focused on various multiview applications wherein a viewer is able to see only one pair of stereo video from a specific viewpoint and another pair of stereo video from a different viewpoint. One of the most feasible approaches for such multiview applications has turned out to be such wherein only a limited number of input views, e.g. a mono or a stereo video plus some supplementary data, is provided to a decoder side and all required views are then rendered (i.e. synthesized) locally by the decoder to be displayed on a display.
When encoding 3D video content, video compression systems, such as Advanced Video Coding standard H.264/AVC or the Multiview Video Coding MVC extension of H.264/AVC, High Efficient Video Coding standard HEVC or Multiview extension of HEVC plus depth, or 3D extension of HEVC may be used.